I have lived in Germany before, but never heard about this old custom of the Rhineland region: Maibaum stellen (erect May trees).
I found out the night before 1st May, when I saw groups of young men having fun in big cars, organized with loud music, some drinks and … trees on top of the cars!
Soon someone explained: boys decorate birch trees with colorful ribbons and often a heart with the name of the girl, and place them in front of the house of a girl who they would like to date/marry.
No matter how difficult that is, they carry the trees to the strangest places and they even climb on balconies with the help of their friends. Ideally, the girl does not find out who her cavalier was. She only finds out after one month, when the tree will be taken away by the same men.
You may imagine just few trees here and there. No. The trees are everywhere! These trees decorate the cities during the entire month of May, which gives them such a wonderful romantic touch…